Definition of infantile:
asymptomatic, full-grown, young, childlike, babyish, jejune, autoimmune, full-blown, fully-fledged, benign, developed, grown, clinical, catching, cherubic, childish, chronic, communicable, puerile, fully-grown, kiddish, advanced, naive, congenital, full-fledged, infantine, infant, baby, youth, growth, acute, childlike, immature.
beginning (part of speech: adjective)
- juvenile (part of speech: adjective)
- "The Romance of Names", Ernest Weekley.
- "Kildares of Storm", Eleanor Mercein Kelly.
They were fitted for the new reading public for this reason; the constant repetition of the same characters, events, scenes, plots, gave their infantile minds the pleasure which children find in having a story told over and over in exactly the same terms.- "Imaginary Interviews", W. D. Howells.